We use \(\mu \)  to denote the steady value, i.e. the equilibrium expectation. When the difference with the equilibrium expectation is considerably larger than the root of the variance at equilibrium \(\sigma =\langle (x-\langle x\rangle )^2\rangle ^{1/2}\) , the system is far from equilibrium. The period of time from nonequilibrium to equilibrium is called the relaxation time \(\tau _{\rm eq}\)  [1]}[2]}. In our simulation, relaxation time \(\tau _{\rm eq}\)  is estimated by the time when the value of \(\vert m\vert \)  enters the interval (\(\mu -\sigma \) , \(\mu + \sigma \) ), i.e. the band of thermal fluctuations around the equilibrium expectation.
